In developing the world’s first run-off road protection package, Volvo turned to an unlikely source to simulate the forces of the violent crash in order to fine-tune each of the systems required for occupant protection.
Crash testing is fine for making sure airbags deploy properly and the safety cell stays intact, but how do you simulate the forces on seats to make sure they are absorbing lateral and vertical impacts, or that seatbelts are securing occupants not just on a plane but gyroscopically?
You use a simulator, of course.
The idea reportedly came to Volvo Cars’ safety expert Anders Axelson during a visit to Denmark’s Legoland with his daughters.
“Watching people being thrown in all directions during a ride in the ‘Robocoaster,’ I suddenly realised that those rapid, random movements resembled the violent forces occupants in a run-off road crash are exposed to,” he explains.
Axelson and his team had been collecting data on run-off crashes in order to develop a protection system for different types of crashes when vehicles leave the roadway. There were three main scenarios the team had been studying — Ditch, where the vehicle slides off into a deep roadside depression; Airborne, where the shoulder drops off significantly into the surrounding territory, causing the wheels to lose contact with the ground; and Rough Terrain, where the vehicle encounters all levels of terrain and protruding obstacles after it leaves the pavement — each of which presented its own challenges in protecting the occupants of the vehicle cabin.
“The engineers developed promising solutions to actively retract the occupants in order to keep them in (their seats). But since running complete cars into the terrain is a time-consuming and expensive test method, we needed a quicker and cheaper solution to evaluate the ideas,” Axelson recalls.
Watching people being tossed about in the Robocoaster, started Axelson searching for a simulator that could be programmed with the exact movement patterns the team had gathered from real world run-off road crashes.
Axelson found that ABB Robotics had the technology and the knowledge to program a precise-movement machine to mimic the random pattern of forces during such a crash. The multi-axial robot is then fitted with a seat into which is strapped a crash-test dummy to gather information.
“It worked brilliantly,” concludes Axelson
The result is the world-first run-off road protection package that includes rapid electrical safety belt retraction and unique energy-absorbing functionality in the seat (to absorb the vertical forces that occur in a hard landing in the terrain beyond the pavement). The technology made its debut on the new XC90 luxury sport utility vehicle, and will be available on upcoming Volvo cars.
“The most valuable result from the ‘Robocoaster’ tests is probably the insight into how well the safety belt retraction interacts with the enhanced side support in our new seat generation,” says Axelson.